UWP and Xamarin apps can use XAML, so it's not like the underlying ideas of WPF/Silverlight are dead.
WPF is a lot more than just a markup language for object graphs. Heck, the features I consider most essential and important to WPF (data binding, templating, and the idea that controls only encapsulate behaviour) have nothing to do with XAML at all.
But aren't all those features you mentioned part of UWP also?